Colocasia plant named ‘Black Swan’

ABSTRACT

A new cultivar of Colocasia plant named ‘Black Swan’ characterized by large, lustrous, dark greyed-purple leaves; stemless, vigorous, tropical, perennial habit and multiple long spadix flowers surrounded by enrolled burgundy spathes.

Botanical classification: Colocasia hybrid.

Cultivar designation: ‘Black Swan’.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is co-pending with the U.S. Plant Patent Applicationsfor two other plants from the same breeding program with the sameparents, namely, Colocasia plant named ‘Black Goblet’ (U.S. Plant patentapplication Ser. No. 15/932,772) and Colocasia plant named ‘DistantMemory’ (U.S. Plant patent application Ser. No. 15/932,164).

BACKGROUND OF THE PLANT

The present invention relates to a new and distinct hybrid of Colocasia,hereinafter referred to by its cultivar name, ‘Black Swan’. Colocasia isa tropical genus in the Araceae family.

The new cultivar was derived from a controlled breeding program underthe direction of by the inventor at a wholesale perennial nursery inZeeland, Mich., USA. The overall purpose of the breeding program was tomake selections of Colocasia plants with colorful foliage, good growthrate and that are well suited for landscape or containers. ‘Black Swan’arose from a cross performed in May 17, 2012 between Colocasia ‘BlackCoral’ U.S. Plant Pat. No. 23,896 as the female and the male parent was‘Thailand Giant’ (not patented). ‘Black Swan’ was given the breeder code12-07-01 prior to naming.

Asexual propagation of the new cultivar was first accomplished by invitro propagation using shoot tip culture in 2014. To those skilled inthe art shoot tip tissue culture produces propagules of identicalcharacteristics to those of the original plant. Asexual propagation of‘Black Swan’ by shoot tip tissue culture has shown that thecharacteristics of the new cultivar are stable and reproduce true totype in successive generations.

No plants of Colocasia ‘Black Swan’ have been sold, in this country oranywhere in the world, prior to the filing of this application, nor hasany disclosure of the new plant been made prior to the filing of thisapplication except that which was disclosed within one year of thefiling of this application, and was either derived directly orindirectly from the inventor.

SUMMARY OF THE INVENTION

Plants of Colocasia ‘Black Swan’ have not been observed under allpossible environmental conditions. The phenotype may vary somewhat withvariations in environment such as temperature, available water,fertility and light intensity without, however, any variation ingenotype.

The following traits have been repeatedly observed and are determined tocomprise the unique characteristics of the new plant and distinguish itas a new and distinct Colocasia different from all other Colocasia knownto the inventor:

-   -   1. Large, lustrous, dark greyed-purple leaves;    -   2. Large, upright, stemless, vigorous, tropical perennial habit;    -   3. Multiple, long, spadix per leaf axil.    -   4. Solitary growth habit with rare basal shoot development.

BRIEF DESCRIPTION OF THE DRAWINGS

The photograph of the new plant demonstrates the unique traits and theoverall appearance of Colocasia ‘Black Swan’. The colors are as accurateas reasonably possible with color reproductions of this type. Variationsin ambient light spectrum, source and direction may cause the appearanceof minor variation in color. The plants used in the photograph weretwo-year-old plants grown initially in a greenhouse then set out earlysummer in a shaded trial garden at a wholesale perennial nursery inZeeland, Mich. with supplemental water and fertilizer when needed. Noplant growth regulators or pinching have been used.

FIG. 1 shows a close-up of the flower with ruler for size reference.

FIG. 2 shows a fully grown leaf with the shine and slight undulationsand dimpling.

The nearest comparison varieties known to the inventor are theco-pending siblings and ‘Black Sapphire Gecko’.

In comparison to the female parent the new plant is larger in habit andindividual leaf blades are held more horizontal. ‘Black Coral’ alsoproduces great numbers of basal shoots. In comparison to thegreen-leafed male parent the new plant is shorter with smaller leaves,has darker leaf blades and petioles and a lustrous adaxial leaf surface.

‘Black Swan’ has larger leaf blades than ‘Black Sapphire Gecko’ andleaves are held more outright and less cernuous than ‘Black SapphireGecko’. Compared with ‘Distant Memory’ the new plant has more lustrousupper leaf surfaces and is larger in habit with fewer basal side shoots.Compared with ‘Black Goblet’ the new plant has a flatter and less cuppedleaf, and the leaves are larger and darker greyed-purple.

DETAILED BOTANICAL DESCRIPTION

The following is a detailed description of two-year-old plants of thenew cultivar as grown initially in a greenhouse and then outdoors forthe summer of the second season, in a shaded trial garden in Zeeland,Mich. No plant growth regulators have been used. Plants of the newcultivar have not been tested under all possible conditions. Thephenotype may vary with changes in environmental, climatic, and culturalconditions without change however in the genotype. The color referenceis in accordance with the 2015 edition of The Royal HorticulturalSociety Colour Chart except where general color dictionary terms areused.

-   Botanical designation: Colocasia hybrid;-   Cultivar denomination: ‘Black Swan’;-   Parentage: The female or seed parent is ‘Black Coral’ and the male    or pollen parent is ‘Thailand Giant’;-   Asexual propagation: Shoot tip tissue culture;-   Time to initiate roots: About two weeks;-   Time to finish in a 7 liter container: About three months from a 2.5    cm plug;-   Growth rate: Vigorous;-   Plant habit: Tropical herbaceous perennial; upright; acaulescent;    upright; clumping; tuberous rhizomes formed at base of plant;-   Plant size: About 180.0 cm tall and about 160 cm wide at edges of    leaves;-   Root description: Thick, limited branching; to about 25.0 cm long;-   Root color: Between RHS 182A and RHS 183D;-   Foliage: Simple; alternate; petiolate; sagittate to cordate;    slightly and irregularly undulate; slightly dimpled; base cordate to    auriculate, lobes frequently imbricate; apex broadly acute to    slightly cuspidate; margin entire; adaxial surface lustrous; abaxial    dull; both adaxial and abaxial glabrous;-   Leaf size: Average about 84.0 cm long and about 62.0 cm across; base    fused about 13.5 cm below petiole attachment; basal auricles    extending about 30.0 cm below petiole;-   Leaf attitude: Outwardly to semi-drooping in maturity;-   Leaf color: Mature adaxial blend between RHS N187A and RHS N189A    under greenhouse conditions and nearest RHS N186A in trial garden,    mature abaxial blend between RHS 189A and RHS 177C under greenhouse    conditions and blend between RHS 146A and RHS 187A in trial garden;-   Veins: Pinnate; glabrous abaxial and adaxial; main veins broad,    nearly smooth adaxial and costate and rounded abaxial; abaxial    midrib to about 19 mm across, lateral pinnate veins to about 4.0 mm    across and secondary veins less than 0.3 mm across; adaxial veins    less defined dimension;-   Vein color: Mature adaxial blend between RHS 146A and RHS 187A,    mature primary and secondary abaxial veins between RHS N186C and RHS    187B;-   Petiole: Sarcous; concavo-convex to involute; petiole attitude    upright to semi-outright; average of about 96 cm in length, about 25    mm deep at base, about 22 mm across laterally at base and 6 mm    across at blade; glaucous abaxial and adaxial;-   Petiole color: Abaxial nearest N186A, between adaxial surface    between 189A; in color on the inner surface, 5 cm in diameter and 8    cm in length, glabrous on both surfaces and glossy surface on the    outer surface.-   Inflorescence description: Spadix with spathe; female portion    proximal to male portion on same peduncle; beginning to bloom about    mid-August once plants are mature; producing typically four    inflorescences per leaf axil.-   Inflorescence bud: Linear to clavate with swollen rounded base; apex    narrowly acute; about 18.0 cm long and about 2.2 cm wide in swollen    base;-   Bud color: Variable; nearest RHS N186D in distal areas and RHS N186B    in swollen base;-   Inflorescence size: Average of about 21.0 cm in length and 2.5 cm    wide in female portion and 1.7 cm wide in male portion;-   Flower fragrance: None detected;-   Lastingness of inflorescence: About 2 to 3 weeks.-   Flower quantity: Average of about 200 female sessile flowers sessile    to spadix; average about 500 sessile male flowers per spadix;-   Spathe: Hooded involute bract; subtending spadix and completely    enveloping spadix; lanceolate; with acute apex and truncate base;    margin entire;-   Spathe size: Average of about 20.5 cm in length, about 9.0 cm in    width if unrolled and 17.0 mm diameter at base when rolled;-   Spathe color: Abaxial nearest RHS 186D; adaxial proximally nearest    RSN186D and distally nearest RHS 187A;-   Spadix: Male portion with acute apex, average about 4.5 cm in length    and 5 mm in width, color nearest RHS 161D; female portion    ellipsoidal in shape, an average of 3.5 cm in length and 15.0 mm in    width, color nearest RHS 161D;-   Reproductive organs: Have not been observed to develop;-   Fruit and seed: Have not been observed;-   Diseases and resistance: Resistance to pests and diseases beyond    that common for other Colocasia cultivars has not been observed. The    plant is tropical and grows best with ample moisture, good drainage    and warm temperatures. The complete hardiness of the new plant has    not been tested.

It is claimed:
 1. A new and distinct cultivar of Colocasia plant named‘Black Swan’ as herein illustrated and described.